Update registry tests to test schema 2 manifest pushes and pulls

Note that tests for manifest *lists* will be in a following commit

test/registry/protocol_fixtures.py

@@ -6,6 +6,7 @@ import pytest
 from Crypto.PublicKey import RSA
 from jwkest.jwk import RSAKey
 
+from test.registry.fixtures import data_model
 from test.registry.protocols import Image, layer_bytes_for_contents
 from test.registry.protocol_v1 import V1Protocol
 from test.registry.protocol_v2 import V2Protocol
@@ -47,7 +48,8 @@ def sized_images():
     Image(id='parentid', bytes=parent_bytes, parent_id=None, size=len(parent_bytes),
           config={'foo': 'bar'}),
     Image(id='someid', bytes=image_bytes, parent_id='parentid', size=len(image_bytes),
-          config={'foo': 'childbar', 'Entrypoint': ['hello']}),
+          config={'foo': 'childbar', 'Entrypoint': ['hello']},
+          created='2018-04-03T18:37:09.284840891Z'),
   ]
 
 
@@ -105,9 +107,39 @@ def v1_protocol(request, jwk):
   return request.param(jwk)
 
 
-@pytest.fixture(params=[V2Protocol])
-def manifest_protocol(request, jwk):
-  return request.param(jwk)
+@pytest.fixture(params=['schema1', 'schema2'])
+def manifest_protocol(request, data_model, jwk):
+  return V2Protocol(jwk, schema2=(request == 'schema2' and data_model == 'oci_model'))
+
+
+@pytest.fixture(params=['v1', 'v2_1', 'v2_2'])
+def pusher(request, data_model, jwk):
+  if request.param == 'v1':
+    return V1Protocol(jwk)
+
+  if request.param == 'v2_2' and data_model == 'oci_model':
+    return V2Protocol(jwk, schema2=True)
+
+  return V2Protocol(jwk)
+
+
+@pytest.fixture(params=['v1', 'v2_1'])
+def legacy_pusher(request, data_model, jwk):
+  if request.param == 'v1':
+    return V1Protocol(jwk)
+
+  return V2Protocol(jwk)
+
+
+@pytest.fixture(params=['v1', 'v2_1', 'v2_2'])
+def puller(request, data_model, jwk):
+  if request == 'v1':
+    return V1Protocol(jwk)
+
+  if request == 'v2_2' and data_model == 'oci_model':
+    return V2Protocol(jwk, schema2=True)
+
+  return V2Protocol(jwk)
 
 
 @pytest.fixture(params=[V1Protocol, V2Protocol])
@@ -115,16 +147,6 @@ def loginer(request, jwk):
   return request.param(jwk)
 
 
-@pytest.fixture(params=[V1Protocol, V2Protocol])
-def pusher(request, jwk):
-  return request.param(jwk)
-
-
-@pytest.fixture(params=[V1Protocol, V2Protocol])
-def puller(request, jwk):
-  return request.param(jwk)
-
-
 @pytest.fixture(scope="session")
 def random_layer_data():
   size = 4096